The temperature in Toronto plummeted 24 degrees in 12 hours, landing at a bone-chilling -15 degrees Celsius despite Saturday's bright blue skies and sunshine.

Before noon on Friday, temperatures hovered at a spring-like 9 C just before noon yesterday. By 2 a.m., Pearson Airport's weather monitors were reporting temperatures well below -10 C.

One good-hearted Torontonian was seen dropping off hot coffee and sandwiches to the homeless, many of whom spent a brutal night outside.

The city has placed an extreme cold weather alert in effect, which is issued to open up extra shelter beds to get the homeless off the streets and out of the bitter weather.

The city's 24 hour helpline for those who need shelter can be reached at 416-338-4766.